Steel conversion vessel



Aug. 0, 1966 J. WALKER 3,269,716

STEEL CONVERSION VESSEL Filed Nov. 26, 1962 INVENTOR.

JOHN WALKER United States Patent 3,269,716 STEEL CONVERSION VESSEL John Walker, Walnut Creek, Calif., assignor to Kaiser Industries Corporation, Oakland, Calif., a corporation of Nevada Filed Nov. 26, 1962, Ser. No. 261,243 (Filed under Rule 47(b) and 35 U.S.C. 118) 9 Claims. '(Cl. 26635) This invention relates to apparatus for conversion of iron to steel and particularly to a vent assembly used in conjunction with a conversion vessel.

In a process for converting iron to steel, a stream of oxygen is blown against the raw material contained in a refractory lined conversion vessel of converter that is pivotally mounted whereby it can be moved between a vertical converting position and a tilted discharging or pouring position. The conversion vessel is charged with the proper ingredients to form steel through an open mouth after which a stream of oxygen is directed against the surface of the charge to effect the conversion of the charge to steel. The oxygen is introduced into the vessel through a conduit called a lance which is usually cooled to prevent its destruction and placed within the vessel the proper distance from the charge.

The process is accompanied by the evolution of a large amount of hot gas which desirably is carried off. Accordingly, it is necessary to provide a vent or vent system positioned over or adjacent to the mouth of the vessel to collect the gas and transport it from the vessel when the vessel is in the converting or operating position with the lance inside of the vessel.

The presence of such a vent or vent assembly above or adjacent the mouth of the vessel causes many problems in the operation of the process. To mention a few, the conversion vessel must be charged through the opening or mouth and the presence of a vent system above or adjacent to it obstructs the opening and greatly increases the difiiculty of introducing the charge into the vessel. The oxygen lance must extend into the vessel and therefore, it must :be inserted, removed and manipulated through an opening in the vent or gas exhaust system. As such, the oxygen lance must be raised high enough to clear both the vessel and various elements of the gas exhaust system before it can be either inserted into the vessel or removed from the vessel. Suitable equipment and clearance must therefore be provided to place the lance within or to remove the lance from the vessel. The vessel is discharged by tilting, and a vent assembly in close proximity with its mouth must not interfere with discharging of the vessel. Making either the vent assembly or vessel movable with respect to the other is quite difiicul-t because both are extremely large and cumbersome devices that must be insulated, water cooled or both and spacing them to leave enough clearance for proper tilting of the vessel may permit large volumes of air to be needlessly drawn into the vent system which causes burning of combustible gas and greatly increases the volume of gas to be handled.

This invention provides a unique means for venting a conversion vessel used in the oxygen blowing conversion process to eliminate or reduce substantially or reduce substantially all of the above difficulties. The device of this invention provides a gas vent or duct that advantageously is offset from the vertical axis of the conversion vessel so that the vent itself does not obstruct the open mouth of the vessel. The vent, however, may be placed in operative condition by manipulation of one, or preferably two, movable hood segments which, when they are in the extended or joined position, form a hood for collecting the gas from the vessel and for transferring the gas to the vent The hood segments advantageously are provided 3,269,716 Patented August 30, 1966 with cooperative means which form an aperture or opening to receive the lance when the segments are joined, but which separate to free the lance when the hood segments are separated. The cooperating means may form merely a snug opening through which the lance may be manipulated or they may form a clamp which holds the lance tightly in its proper position. The lance-receiving opening may also be relatively large with respect to the lance and independent lance-clamping means may be employed cooperatively with the opening.

The individual hood segments are small compared with the vent assembly or with the conversion vessel and they may accordingly be easily moved with ordinary force-exerting means such as hydraulic or pneumatic cylinders. The hood segments preferably are hinged to the vent or duct assembly and they preferably are constructed as spaced double-walled segments having suitable inlets and outlets to introduce and discharge cooling water from between the walls. The space between the walls may contain bafiles or other means to form passageways directing the flow of cooling fluid. Since the segments are movable away from the vessel month, they can, if desired, be so positioned relative to the vessels mouth as to form a substantially gas tight seal with the vessel when in their extended and joined position.

Generally, the operation of the device is as follows. The hood segments are separated and various ladles, hoppers, chutes and bins introduce the charge into the conversion vessel through the open mouth portion. During the charging portion of the process the open mouth of the vessel is not obstructed by the vent or by the hood segments in that they are in a separated or retracted position. After the vessel is charged, the oxygen lance is moved, for example with an overhead crane, into its operative position so that the tip that discharges oxygen is suitably disposed within'the conversion vessel and with respect to the charge in the vessel. After the oxygen lance has been properly positioned, the hood segments are moved to their joined extended position where they form a hood over the mouth of the conversion vessel and embrace the oxygen lance between the cooperative means on the hood segments that are adapted to receive it. If desired, the hood may be partly or completely closed before the lance is positioned.

The conversion process is initiated by passing oxygen through the lance and against the surface of the charge. During the process large quantities of gas are produced and conducted through the hood and the vent. When the conversion process is completed, the hood segments are separated and the lance released. The lance after being released from the hood segments is removed by lifting it only far enough to clear the mouth of the vessel and the conversion vessel is tilted and discharged without obstruction from the hood or vent. Again, if desired, the lance may be released and removed before the hood segments are separated.

The accompanying drawings show a device embodying this invention and are presented as illustrative of the invention rather than limiting as to its scope.

FIG. 1 is a side elevation view of a conversion vessel and vent and hood assembly embodying this invention, with an alternate arrangement of the vessel and hood assembly being shown in phantom and FIG. 2 is a view of the device illustrated in FIG. 1 with parts broken away taken along the line 2-2 and showing in phantom the open position of the hood segments.

In the drawings a conversion vessel 10 is shown suspended by trunnions 11 so that it hangs from the trunnions with its open mouth 12 facing upwardly. A hood assembly '13 comprised of a plurality of double-walled hood segments '13 is disposed adjacent the mouth 12 in such a fashion that it can be spaced from the vessel or as indicated in dotted lines in FIG. 1, it can envelop or be superposed about the mouth portion 12 of the vessel 10. Hood assembly 13 advantageously is connected to vent or duct 15 by hinge assemblies 15' which include the hinge elements 16 connected to vent assembly 15, hinge elements 17 connected to the hood segments 13', and hinge pins 18 and 19 which interconnect elements 16 and 17. In an advantageous embodiment of the invention the hinge pins are hollow conduits which serve the secondary purpose of carrying cooling water to and from the space between the double walls making up the individual hood segments 13'. To adapt the hinge pins for this purpose, cooling water is introduced through conduit 20 into a sliding sealing member 21 which in turn introduces water into hinge pin 18. Hinge pin 18 terminates in a short length of tube 22 which provides open communication between the interior of the hollow hinge pin 18 and the space between the walls of a hood segment 13'. The cooling water passes through the passageway formed by baffles 22 located in the space between the walls of a hood segment 13' and ultimately discharges into a tube 23 that communicates with the center of hollow hinge pin 19 where the heated water then passes through a sliding seal 25 and out through exhaust conduit 26.

Additional hinge elements 27 connected to the side of a hood segment 13' are adapted to be pivotally connected by pin means 27 to a rod 28 that is operated by a pneumatic or hydraulic means, not shown. Operation of the pneumatic or hydraulic means causes each rod 28 to extend or retract thereby causing the hood elements 13' to pivot around the hinge assemblies 15 connecting the hood elements 13' to the vent 15. Retraction of the rods 28 causes the hood segments 13 to move upwardly and laterally away from the mouth 12 of vessel 10 to provide complete access and adequate clearance between the vent assembly and the vessel when the vessel is tilted. In its operative position the lance 30 extends through the opening formed by the lance-receiving segments 31 which are symmetrical half cylindrical segments connected to a pair of the hood segments 13. As best seen in FIG. 2, when the hood segments 13' are joined the lance is held firmly between segments 31, but when the hood segments 13 are separated the lance is completely released and can be manipulated to any desired position within the vessel or outside of the vessel. During withdrawal of the vessel it need be lifted only high enough to clear the mouth of the vessel.

The operation of the illustrated device can best be described with reference to FIG. 2. When the vessel 10 is charged, the hood segments 13 are in the position shown in phantom, that is, the segments 13' are separated and withdrawn to an inoperative position away from the mouth 12 of the vessel 10. In this position, the mouth of the vessel is exposed and ladles or chutes used in charging may discharge their contents into the vessel 12 without a vent or gas discharge duct obstructing their use. After the vessel 10 is charged, the lance 30 is maneuvered into the proper position within the vessel or converter 10. When the lance is positioned, operation of the pneumatic or hydraulic cylinders moves rods 28 in the proper direction and forces segments 13' to rotate around their hinges and to join forming a hood about the mouth of the vessel. As indicated previously, the hood segments and vessel can be so arranged with respect to each other that the peripheral portions of the closed hood segments and vessel mouth 12 overlap each other whereby the hood will contact the' vessel in a substantially gas tight sealing relationship. In coming together, the bulbous segments 31 on the hood elements 13' form an opening 35 surrounding the lance 30 and embrace the lance tightly, thereby forming a guide for the lance and a means for holding it in its proper vertical position. In the preferred embodiment of the invention the opening 35 formed by bulbous segments 31 is substantially aligned with the vertical axis of the vessel 10 while the vent 15 is offset with respect to 4 the normal vertical axis of the vessel when the vessel is in operating position and the hood segments 13' are extended and joined.

When oxygen is passed through the lance and blows against the surface of the charge, the conversion of the charge to steel is effected, and the gas evolved from the process passes through the hood assembly 13 and into the vent 15 where it is carried away. When the oxygen treating portion of the process is completed, operation of the pneumatic or hydraulic means causes hood segments 13' to separate thereby freeing the lance 30 and providing adequate clearance for tilting vessel 10. The lance 30 is then removed from the interior of the vessel 10 and the vessel 10 is rotated around its trunnion 11 to discharge the molten steel contents. After discharging its contents, the vessel 10 is returned to the upright position and is ready to repeat the process.

Within the broad scope of this invention there may be many variations and modifications to adapt the invention to a specific process. By way of example, the hood may be formed of three or more segments or the segments may be independently movable and not hinged to the vent. The conversion vessel may be oriented in positions other than vertical during the oxygen treating portion of the process in which case the hood segments are suitably arranged to take into account the angle of disposition of the conversion vessel. The lance-receiving opening may be in either hood segment rather than being formed by their juncture, and it may be substantially larger in diameter than the lance and shaped to cooperate with independent lance clamping means. It is evident that all of these and other modifications are within the concept of this invention which should be limited only by the following claims.

What is claimed is:

1. An apparatus for oxygen conversion of steel which comprises a conversion vessel pivotally mounted to move from a normal converting position to a tilted pouring position, said vessel being provided with a mouth opening upwardly when said vessel is in its normal converting position, a vent means adapted to carry gas away from said vessel, said vent means being offset from the vertical axis of said vessel when the vessel is in its normal converting position, a hood extendable from said vent means to a gas-collecting position with respect to the mouth of said vessel when the latter is in its normal converting position, said hood including a pair of separable segments that are retractable from said gas-collecting position, each segment having means which, when the segments are joined, cooperate to form a lance-receiving opening for receiving a lance movable into and out of said vessel and extendable I through said lance-receiving opening.

2. The apparatus of claim 1 further characterized in that when said segments are extended and joined to form a hood, said hood contacts said conversion vessel in a substantially gas-tight sealing relationship.

3. The apparatus of claim 1 further characterized in that said segments are formed with spaced, double walls and are provided with means for introducing cooling water between said walls and withdrawing cooling water from between said walls.

4. The apparatus of claim 1 further characterized in that said hood is constituted of two segments and both segments are hinged to said vent means.

5. The apparatus of claim 1 further characterized in that in its normal converting position the vertical axis of said vessel is normal to its pivotal axis.

6. An apparatus for oxygen conversion of steel which comprises a conversion vessel pivotally mounted to move between a vertical position and a tilted position, said vessel being provided with a mouth opening upwardly when said vessel is in vertical position, a vent means adapted to carry gas away from said vessel, said vent means being olfset from the vertical axis of said vessel when the vessel is in a vertical position, a pair of spaced double-walled segments each connected by a hinge to said vent means and extenclable to a joined position in which they form a hood over the mouth of said vessel when the vessel is in vertical position, means for introducing and removing cooling Water from the hood segments, lance holding means connected to each hood segment and positioned to meet and form an opening when the hood segments are extended and joined, for receiving a lance which is movable into and out of said vessel and extendable through the lancereceiving opening.

7. The apparatus of claim 6 further characterized in that said hinge includes a hollow pin connected to a source of cooling fluid and opening into the space between said double walls.

8. An apparatus for conducting gas from a steel conversion vessel having an open mouth from which gas discharges which comprises a plurality of segments movable to and retractable from a joined, extended position in which said segments act cooperatively to form a hood, portions of said hood when in extended, joined position forming an opening in gas-collecting relationship with the mouth of said vessel, and an opening in gas-discharging relationship with a vent, bulbous elements on two of said segments which act cooperatively when said hood segments are extended and joined to form an aperture in said hood through which a conduit can be inserted through said hood, said open mouth and into said vessel;

9. The apparatus of claim 8 further characterized in that said aperture formed by the bulbous elements is of such a size that the conduit is firmly held by said bulbous elements in a predetermined position.

References Cited by the Examiner UNITED STATES PATENTS JOHN F. CAMPBELL, Primary Examiner.

JAMES H. TAYMAN, JR., Examiner.

D. S. LILLY, Assistant Examiner. 

1. AN APPARATUS FOR OXYGEN CONVERSION OF STEEL WHICH COMPRISES A CONVERSION VESSEL PIVOTALLY MOUNTED TO MOVE FROM A NORMAL CONVERTING POSITION TO A TILTED POURING POSITION, SAID VESSEL BEING PROVIDED WITH A MOUTH OPENING UPWARDLY WHEN SAID VESSEL IS IN ITS NORMAL CONVERTING POSITION, A VENT MEANS ADAPTED TO CARRY GAS AWAY FROM SAID VESSEL, SAID VENT MEANS BEING OFFSET FROM THE VERTICAL AXIS OF SAID VESSEL WHEN THE VESSEL IS IN ITS NORMAL CONVERTING POSITION, A HOOD EXTENDABLE FROM SAID VENT MEANS TO A GAS-COLLECTING POSITION WITH RESPECT TO THE MOUTH OF SAID VESSEL WHEN THE LATTER IS IN ITS NORMAL CONVERTING POSITION, SAID HOOD INCLUDING A PAIR OF SEPARABLE SEGMENTS THAT ARE RETRACTABLE FROM SAID GAS-COLLECTING POSITION, EACH SEGMENT HAVING MEANS WHICH, WHEN THE SEGMENTS ARE JOINED, COOPERATE TO FORM A LANCE-RECEIVING OPENING FOR RECEIVING A LANCE MOVABLE INTO AND OUT OF SAID VESSEL AND EXTENDABLE THROUGH SAID LANCE-RECEIVING OPENING. 